Cooling Ability/Capacity and Exergy Penalty Analysis of Each Heat Sink of Modern Supersonic Aircraft.

Yu-Feng Mao,Jia-Xin Li,Yun-Ze Li,Kai Xiong,Ji-Xiang Wang

doi:10.3390/e21030223

Abstract

The aerospace-based heat sink is defined as a substance used for dissipating heat generated by onboard heat loads. They are becoming increasingly scarce in the thermal management system (TMS) of advanced aircraft, especially for supersonic aircraft. In the modern aircraft there are many types of heat sinks whose cooling abilities and performance penalties are usually obviously different from each other. Besides, the cooling ability and performance penalty of a single heat sink is even different under different flight conditions—flight altitude, Mach number, etc. In this study, the typical heat sinks which are the fuel mass, ram air, engine fan air, skin heat exchanger, and expendable heat sink will be studied. Their cooling abilities/capacities, and exergy penalties under different flight conditions have been systematically estimated and compared with each other. The exergy penalty presented in this paper refers to the exergy loss of aircraft caused by the extra weight, drag and energy extraction of various heat sinks. The estimation models, as well as the results and discussion have been elaborated in this paper, which can be can be used to further optimize the TMS of modern advanced aircraft, for example, the layout design of various heat sinks and the improvement the control algorithm.

Highlights

Nowadays, modern advanced aircraft suffer from severe thermal management issues caused by the reduction in the cooling ability of traditional heat sinks and the increase in the head load of the aircraft itself [1,2]
The thermo-physical parameters of ram air (RA), engine fan air (EFA) and expendable heat sinks (EHSs) at any time, such as their thermal conductivity, special heat and special enthalpy. are those determined by the National Institute of Standards and Technology (NIST: Gaithersburg, MD, USA) in this study
In order to facilitate the design and optimization of the thermal management system (TMS) for the increasingly severe thermal problems of modern advanced aircraft, this paper presents various models for estimating the cooling abilities/capacities of heat sinks and the exergy penalty caused by each heat sink

Summary

Introduction

Modern advanced aircraft suffer from severe thermal management issues caused by the reduction in the cooling ability of traditional heat sinks and the increase in the head load of the aircraft itself [1,2]. Due to the increasing flight altitude and Mach number, the cooling ability of traditional heat sinks is reduced significantly [3]. The increasing Mach number will lead to a rapid rise in the total/stagnation temperature of ambient heat sinks such as ram air (RA) and fuselage skin, and the high altitude will result in rarefied atmosphere which could make the source of the heat sink less available. The aerodynamic shape and high stealth of the modern advantage aircraft make it even more difficult to obtain ambient heat sinks, resulting in a serious decrease in their cooling ability [4]. The decrease in ambient heat sinks’ cooling ability will cause an increasing dependence on the fuel heat sink [5].

Methods

Results

Conclusion